Memory spec terms
If you're not sure if a module is right for your system, use the Crucial Memory Advisor tool for a list of guaranteed compatible modules.

NON-ECC/Non-parity Most desktop and laptop computers take NON-ECC or Non-parity memory.

ECC/Parity ECC or parity modules look for errors in data and are most often found in servers and other mission-critical applications used by large networks and businesses.

Unbuffered Most PCs and workstations use unbuffered memory which is faster than registered memory.

Registered/Buffered Registered or buffered modules delay all information transferred to the module by one clock cycle. This type of memory is primarily used in servers.

Fully buffered Designed for next-generation servers, features an advanced memory buffer.

CL CAS (column address strobe) latency, which is the number of clock cycles it takes before data starts to flow after a command is received. Lower CL is faster. Modules with different CL can be mixed on a system, but the system will only run at the highest (slowest) CL.

240-pin DIMM

A dual inline memory module (DIMM) consists of a number of memory components (usually black) that are attached to a printed circuit board (usually green). The gold pins on the bottom of the DIMM provide a connection between the module and a socket on a larger printed circuit board. The pins on the front and back of a DIMM are not connected to each other.

240-pin DIMMs are used to provide DDR2 SDRAM memory for desktop computers. DDR2 is a leading-edge generation of memory with an improved architecture that allows it to transmit data very fast.

Each 240-pin DIMM provides a 64-bit data path (72-bit for ECC or registered or Fully Buffered modules). (The Ballistix™ and Ballistix Tracer™ high-performance memory do not come in 72-bit or registered modules.)

To use DDR2 memory, your system motherboard must have 240-pin DIMM slots and a DDR2-enabled chipset. A DDR2 SDRAM DIMM will not fit into a standard SDRAM DIMM socket or a DDR DIMM socket.

The number of black components on a 240-pin DIMM can vary, but it always has 120 pins on the front and 120 pins on the back, for a total of 240. 240-pin DIMMs are approximately 5.25 inches long and 1.18 inches high, though the heights can vary. While 240-pin DDR2 DIMMs, 184-pin DDR DIMMs, and 168-pin DIMMs are approximately the same size, 240-pin DIMMs and 184-pin DIMMs have only one notch within the row of pins. The notch in a 240-pin DDR2 DIMM is closer toward the center of the module.

Put this kit into a Packard Bell istart F2310 with an SIS671 chipset. Having put the first stick in the bios recognised it OK ut having put the second stick in the bios showed the memory increase to 2.6gb extended rather than the 4gb total I was expecting. The bios shows version si671V11 dated 25/6/07 so I thought about flashing the bios with a newer version but cannot seem to find a link to download. Please help.

Try each module alone in each of the slots. If they both work and show as 2GB then it is not a RAM or slot problem as such. A BIOS update could solve the issue but this is a product of the system manufacturer so we cannot supply a link or advise on it. Contact Packard Bell or check the motherboard make and model inside and contact them.

Answered on 12/12/2011 by Crucial Support from Meridian, Idaho

Q:

My computer is running extremely slow (no viruses etc). I currently have 2gb ram with windows 7 ultimate. Will another 4 gb of ram make a difference? Also, what else could be done to improve my pc's speed which will be compatible with my machine? Thanks.

According to the scanner you have an nForce430 motherboard with 4 slots. This can support up to 8GB - 2GB per slot and installation in pairs is favoured. The pair sizes can be mixed for example 2 x 1GB + 2 x 2GB. Two speeds are supported – 667MHz (PC2-5300) and 800MHz (PC2-6400). The speed the RAM can run at depends on what the memory bus speed is set to in your BIOS. You can check what this is set to, match the speed of the current RAM (check the label or refer to the scanner results) or just opt for the faster speed and it will clock down to the slower speed if necessary. They are the same price. Increasing the RAM on a system is the most effective way to improve the speed and performance and the rule is the more the better. However, only a 64-bit version of Windows will address and utilize the full 4GB. Otherwise, with a 32-bit version only about 3GB-3.5GB will be seen and used so check this first.You can view and order parts from here:http://www.crucial.com/uk/store/listparts.asp?model=nForce430+(4+DIMM+Slots)